Hi Akis.
It depends whether you want an OPC or a Specialist to do it. If your car is older than say three or four years and the service history includes a mixture of OPC's and specialists, then I'd go for specialists every time - their labour is less than half the cost and their parts are also cheaper but you tend to get the same expertise, care and attention.
I use Autowerke in Norwich. The guy's name is Matthew and he recently serived my 99 Boxster and ran all the checks through the computer/engine management that an OPC would for a fraction of the cost. He's also an ex-Lancasters boy and has been servicing Porsches for 17 years now so he knows his stuff.
Check him out. I have a 2000 996 C2 TipS and that will be going there in May. I have total confidence in his abilities.
As for an OPC opening next to Lind, I hear it'll be with us around July, but it won't make a difference to me - OPC's charge the earth and I wouldn't nexessarily go there unless my car was new.
Hope this helps.