I've been to CJ's Greedy Girl parties & other swingers clubs a few times and, in Scotland anyway, these things are impossible to predict - unfortunately the only guarantee is that there's generally going to be a lot more men than women! One time I went there were some absolutely gorgeous girls & women there, all very game, willing and up for it ...but other times - a bit like Weight Watchers in a Nursing Home really
Whats the talent is going to be like? - Your best bet is to check the forums of a very well known free swingers website beforehand (i dunno if I can mention it here?), run a search for the date of the event and you might find a discussion around 'Who's Going'.
There's a cap on the amount of single guys at all CJ's parties (in fact all swingers events really) but it varies i think - its easy enough to email or phone her and find out.
Another thing - book your place early as you're gonna hear 'Sorry, full for single males' if you don't. You can always cancel later. And forget about phoning the day of the party, there's always a large 'Standby' guest list, and you'll be at the bottom of it!
Ive been to The After Eight in Edinburgh many times a few years back, some nights were amazing, mental nights (free bar lol) - others were downright depressing!
Its all Worth a go though I'd say!