These debates although helpful only help to confuse and/or misinform people unnecessarily.
At the end of the day if you took any two of the same 5 inch diabolos (circus, finesse, taibolo, suns etc), with time and practice you will learn anything you see in tutorials and videos posted on this site (unless bearings are used but thats a whole different issue altogether). If you were to then swap those two diabolos for another type of 5 inch diabolo, again you would have no problem pulling off the same tricks, your technique develops to the level where weight and the axle width etc dont affect you. The only real issues that arise from the various 5 inch diabolos are:
-Budget. Look around, prices tend to shoot up and down. For example original suns are silly expensive now but old style crystals are really cheap in comparison. Circus are normally always around the £20 mark, at one convention last year they were selling two for £30 (buying at conventions is normally cheaper in general).
-Weight. The only point to make here is circus are considered heavy and to be fair a youngster would probably struggle with two over a long practice session. Tuning kits can make them lighter but again this affects the budget side of things with them tending to cost around £11 each.
-Material. Circus/finesse are indestructible and suitable over concrete. Finesse cups are very sensitive to corrections being so grippy compared to other diabolos. Again, there is no reason why you cannt learn to adjust your technique slightly so this isn't an issue. Taibolo, sun, flys etc start off lovely and shiny but will scuff very easily compared to circus/finesse. If you dont mind using diabolos that will get dirty easily but be playable over any surface, use circus/finesse. If you want diabolos that will stay shiny and new providing you use them on the right surface, use the eastern style diabolos.
At the end of the day you can learn anything with any 5 inch diabolo. They're all very good quality and all offer slightly different qualities which you only notice after diaboloing for a while. If it's your first time buying a 'professional' diabolo any of the above will happily do the job, since 95% of becoming good is in developing your technique.
