I've been on Single Bet Calculator since the spring, mostly late at night on the sofa, so this is just my two pence. Found it after a mate mentioned it, not an ad.
The lobby is frankly enormous — a bit over 3,500 games according to the filter counts. NetEnt stuff dominates, so Book of Dead and all the standards all show up. I mostly stick to Play'n GO titles because the volatility suits me. Small annoyance — searching for a specific slot at Single Bet Calculator is more faff than it should be, filters half work.
Live section is almost entirely Evolution, no complaints there. Actual dealers, the stream holds up on 4G, and the game shows like Crazy Time is where I lose most of my money, honestly. Worth saying the British tables are properly staffed in the evenings. If you're weighing up the promos have a look at free bet calculator single instead of trusting a random forum post.
Bonus-wise on Single Bet Calculator is ?100 matched plus 100 spins on Book of Dead. Wagering is 40x which is about par these days. I also got 20 no deposit spins on verification. Min deposit is ?10, sign-up took me maybe five minutes, verification took about 24 hours.
Withdrawals have been fine. Visa and Mastercard land in a couple of days, Skrill and Neteller were same-day for me, and crypto clears fastest. Pulled ?180 out on Tuesday and it landed early. The live chat on Single Bet Calculator was on me within five minutes — actually read my message. Properly licensed for UK players, which is the bit I actually check. No standalone app, which is mildly annoying but the site works fine.