go for the hartke.. it has aluminium cone my friend, who builds very expensive high-end speaker-systems, once told me that a hard, solid cone can produce better lows, because the thin material goes flabbery... thin cone will give you good mids but the low ( 30hz for example ) frequencies fart out. dunno if it's true, but since my car's subwoofer has a bulletproof thick plastic cone, i give him the benefit of the doubt..
i've owned both. the kick backs don't have a lot of power or headroom. and those aluminum drivers do get blown. i never cranked my kb 12 or 15 and both those speakers went within 6 months. i tkink they sound cold as well. the wm 15 however, is one of my favorite amps. it sounds phat and warm as solid states go and has a great low end with a rather quick response, compared to other 15" combos i've played. i'd go with that one because i've heard only negative things from others who have owned kb's too.
i used to have a WM15. GREAT amp. i loved the sound of it. wish i could have kept it. i needed something louder.. which is the main reason i got rid of it. put some more handles on there.. get a little cart/dolly board.. wonderful. i havent much experience with hartke kickbacks.. but the cabinets/heads ive played through do indeed sound very nice. many people have said they blow very easily. of those two.. i say go with SWR.
I own a Kickback 12. I play in a 5 piece band and have no problem with volume. However, keep in mind either of these amps are in the 120 Watt range and are going to need a little help from the PA. I haven't had any reliablity problems with my Hartke, and I push it pretty hard. If I remember right, the SWR has an output for an extension cab, which the Hartke doesn't have. That might be a plus.
