For some time my car has had an annoying vibration only evident around 27 to 30mph that can be felt through steering, more recently it doesn't feel "planted" on the road when driving, just feels vague.
Changed back to the summer wheels last week which are 275 40 20 Pirelli scorpion (winter tyres are same size but Continentals) and the ride feels crap, there's no particular knocks or bangs just a feeling like your driving on the bump stops particularly at the front of the car and everything is felt through steering.

Car has been looked at by Indy on a couple of occasions and there doesn't appear to be any issues with the bushings in the arms and the front ARB bushes were done with genuine bushes and clamps about 12 months 6000 miles ago.
The steering wheel is ever so slightly off centre but car doesn't pull left or right and tyre wear even.
Car has 81k and is running on genuine 20" rims any ideas ? As a last resort Indy suggests alignment at a cost of £150 but I'm loathe to do it for it not to make a difference and then have to redo it if / when arms need doing. Nanocom Evo

Maybe get the wheels rebalanced first? Cheap one.
Have similar symptoms when I get mud stuck in the wheels.

I agree with Hemo, check the wheels. Mine are genuine 20'' and during last swap from winter to summer tires, it was obvious that one wheel had small dent from inside, I was not aware of that. RRS is a heavy vehicle so even slight hole could cause such thing.

I'd get the balancing and alignment done for starters, but it won't cost you £150, should be no more than £60 even if they have to adjust from and rear.

Find an approved Hunter alignment place on www.alignmycar.co.uk and I assure you it will be money well spent.

Most RRS's have terrible alignment from the factory and the money spent now will save irregular wear and premature replacement of the tyres anyway  ON THE WAY: BMW F21 M140i
MERCEDES GL350 - Metallic Navy Blue w/Grey interior

GOING: BMW F31 335D MSport+ xDrive Touring
GONE: Land Rover Discovery 4 HSE - Stornaway Grey w/Black Interior (wish we'd kept it )
GONE: BMW F10 520D MSport - Carbon Black
GONE:MY12 RRS SDV6 HSE Sumatra/Ivory/Grand Black Privacy glass

Thanks for the suggestions, will start with balancing and alignment, does the vehicle have to be put in tight tolerance mode for the alignment, be interesting to see if the garages know this, had a quick look on the alignmycar site, most of my local ones appear to be bodyshops or there is an Ats euromaster which offer the before and after printouts, 4 wheel alignment for £65 Nanocom Evo

I believe it does have to be put in the tight tolerance mode, just check when booking somewhere that they know that, if they aren't aware, then I'd chose another place.

£65 seems a fair price, some do the check for free, then charge 'per adjustment', others charge for the testing (around £30), then charge a smaller amount for each adjustment.  ON THE WAY: BMW F21 M140i
MERCEDES GL350 - Metallic Navy Blue w/Grey interior

GOING: BMW F31 335D MSport+ xDrive Touring
GONE: Land Rover Discovery 4 HSE - Stornaway Grey w/Black Interior (wish we'd kept it )
GONE: BMW F10 520D MSport - Carbon Black
GONE:MY12 RRS SDV6 HSE Sumatra/Ivory/Grand Black Privacy glass

Hi Jaggs,
I had a similar problem I had all for wheels rebalanced last week and it has been fine since
Cost £20.00 for all 4 Wheels  MY08 RR SPORT3.6TD V8 FULLY LOADED, COOLER BOX, GVIF UNIT, PIONEER AVIC-F980DAB HEAD UNIT, RETAINING 4X4 INFO OEM SCREEN AND TS-WX130DA SUB
REAR 9 INCH TOUCH SCREEN HEADREST TV SCREENS, WIRELESS HEADRESTS, IN-CAR WIFI MIRROR BOX FOR WATCHING INTERNET TVIE BBC I-PLAYER ETC... FROM ANDROID, WINDOWS AND IOS PHONES ON THE GO ON ALL SCREENS

Had the alignment done this morning and it feels better thanks for all the suggestions folks
 Nanocom Evo

Good to hear  ON THE WAY: BMW F21 M140i
MERCEDES GL350 - Metallic Navy Blue w/Grey interior

GOING: BMW F31 335D MSport+ xDrive Touring
GONE: Land Rover Discovery 4 HSE - Stornaway Grey w/Black Interior (wish we'd kept it )
GONE: BMW F10 520D MSport - Carbon Black
GONE:MY12 RRS SDV6 HSE Sumatra/Ivory/Grand Black Privacy glass

Hi Jaggs, my 07 Sport is showing the exact same symptoms. Did you have it done in Leeds, if so where did you go. Cheers Pete

Had it done at Master Cars, Birstall, near ikea, they are a body repair shop with the hunter equipment. Nanocom Evo

Really close to me, cheers

Green oval will be close too tnen, good Indy Garage Landrover specialist, if you haven't had the oil pump done on your RRS then I would recommend you do before the tensioner snaps and kills the engine, 2007 are prone for it, I had to have a new engine. Nanocom Evo

cheers Jaggs, i know Green Oval, will check my service history to see if Oil Pump got done with Cambelt change. My alignment was way out (see image) and sorted thanks to Master Car, still got an issue with rough steering and DSC. Forum suggests it could be rear bushes or steering pump fluid. But Alignment issue was a good catch thanks to you, Master Car tech said i would have wreck my new tyres if i continued driving as was.