Definitely the Beau Rivage. They have a fabulous high-limit lounge, amazing service, great food, etc.  And a good selection of slots.  My favorite slots are the $10 double diamonds. I got a very nice handpay on one of those machines just last month, and I've seen several on them.  I also got a good handpay earlier this summer on a $25 Pinball at IP Biloxi. I don't normally go to the IP because it seems like they're a bit tighter, but obviously it worked out for me that time :-) Hard Rock has a good high-limit selection and nice atmosphere, but I've never had much luck there. Overall Biloxi is great for high limit slots; you can find plenty of $100 machines in town and even some $500.  

Good luck!

Thanks, Mississippi Queen!  Sorry for the delay; that's very helpful.  I'm a B Connected Emerald member, so will definitely want to try the IP, but I'll check out the Beau, too.  I know you mentioned you don't go to the IP much, but do you happen to know what they have in $100 machines?

Oh, I didn't know they had any B Connected casinos in Atlantic City! I believe the $100 slots at IP Biloxi are Double Gold, Double Diamond and Red, White and Blue. Sorry I can't recommend one; the $100 machines are beyond my bankroll. :-)

Thanks again, MQ! Actually I'm from Memphis and usually play in Tunica. The AC in my handle stands for air conditioning :-)  Haven't been to Biloxi since '08; really looking forward to seeing how it's changed since then.  I'll let y'all know how it goes.  Thanks again for the help.