for the rear youve got 3 real choices: Maxxis: fairly pricey, very grippy, very puncture resistant, very heavy ; High Roller, Minion, heavy Schwalbe: not all that grippy, fairly bad puncture resistance, very light; Big betty... continental: very pricey ( £40 a tyre ), on a par with maxxis for grip, moderate puncture resistance, nearly as light as the schwalbe ; Rain king, runner Queen, Der Kaiser, Michelin: Not commonly used in the trials world, fairly grippy, good puncture resistance, no idea on price though, moderately heavy..although not the same heft as maxxis i don't think WTB tyres aren't really worth bothering with in my experience...fine for light xc extra, but cant really hack trials...probably be usable for a front tyre, but i would have thought that's about it