please anybody give advice.
Firstly wait until after National Offer Day (one week to go); if you get a place you want then you can just accept and all is done. If you don't get an offer (remember the majority of TGS stage 2 candidates will not get an offer) then you need to accept an alternative (and for Independent schools likely pay a deposit); from experience good Independent schools are happy to wait until March 3rd for an initial decision.
Subsequently you may choose to go on a waiting list (e.g. there will probably be 10+ TGS offers after national offer day as places are declined); if you do that (and it only makes sense if you were near the cut-off) then you need to accept that you will lose any deposit paid to an independent.
IMHO Which school you ultimately choose (subject to having to having met the acceptance criteria) is purely a personal and subjective choice; can't really advise.