I'm looking to get a decent used reverb pedal to use with a Pro Jr amp. Mainly want an "on all the time at a low level" type reverb. Watching 4 on eBay right now. Not sure how high the bidding will go. Trying to stay under $60. Any opinions on which of these is better? : boss rv-2, boss rv-5, Holy Grail, and mod-tone coliseum reverb. Thx!