Does that mean that you would play against a CSM ?
The games in London are not very good.
You cannot just walk into a casino and play BJ.
You have to be a member in good standing.
You can apply and wait for 24 hrs., I think, and see if they permit you to play.
I also believe that a member of the club can escort you in though.
Caveat: Card Counters have had their money confiscated on occasion, but that hardly applies to you.
Which is best can be a bit subjective. It depends a lot on what you are looking for.
You'll find a number of London casinos discussed in previous threads in this subforum.
Napoleon's, Leicester Sq. has traditionally been viewed as 'best'. It offers 4 decks, with a £5 minimum at a few tables, but the penetration has been seen to become poor recently.
Next door, on the other hand, at the Empire, they have gone from 6 to 8 decks, but apparently they have also introduced full insurance (rather than even money only). I don't know what the penetration is like. The min bet is £10.
A short walk away is the Golden Nugget. Same rules as the Empire (and presumably others in the LCI chain), but the minimum is £5.
Elsewhere you will mostly find 6-deck games with a £5 or £10 minimum. There is one place I know of that offers a £2 minimum at certain times of day, but that is usually with a CSM.
Some don't require any ID or membership. (Though you can still become a member, if you wish, and gain a few perks.) That's true of Napoleon's and the LCI chain, I think.
Others require you to become a member on your first visit (requiring ID). Thereafter you just show you membership card to gain entrance. You don't have to hand the card over at the gaming tables, though there may be 'loyalty points' to be gained by doing so, (The closest thing we get to comps here.)
Some chains require you to become a member separately at each of their casinos, while others just require you to register once, and then you can visit any in the chain.
My information may be dated, but it certainly used to the case.
If you're not adverse to travelling out of London for a game, then you could do worse than visit one of the Galas a bit out of town. There are two in Northampton with £3 mins on the BJ tables, and the one in Leicester has BJ at a quid min before 2.00pm, after which they open the main gaming floor and the min goes up to £2. Usual 6 deck shoe games with the pentration being dealer dependent - usally around the 75%ish mark in my experience though. Might be worth one of those el-cheapo off peak return train tickets?
If it has to be London then I think Napoleon's in Leicester Square comes top of the list, although you can forget about all of the back-counting stuff anytime after 6.00pm. Oh, and be aware that the staff there are more savvy than in other places I've played at and will pick up on hefty bet spreads on large bets.
London's like Munich - there is nowhere cheap from May/June onwards unless you want to suffer a dive somewhere. I would suggest taking a look at the London underground map, and look for accommodation or a camping site close to a tube station towards the end of the lines - ie Barnet in North London, Upminster in the East etc. Travel time into Central London will be around 30 to 40 minutes on the tube.