from my experience with them, they're not very good and tear easily. the available compounds give very little grip on urethane surfaces (like RCP). i've tried them on both circuits at nanotrax and have no good feedback to report. on the other hand, the X-Power Foam Racing Wheels are great on the hard, smooth, urethane tiles on F2L but give an inconsistent feel on the softer surface on F1R. foam tends to lose its grip relatively quickly on high traffic circuits that alternate foam/rubber, the foam easily picks up tire wear residue. you can always use a WD-40 pen for grip assistance but it wears off after about 10-15 mins and can leave trails on light colored surfaces.
if you're interested in the XP Foam Racing Wheels, you can get those at our online shop, AtomicMods is our retailer in the USA, but they have yet to stock this item. get in touch with them if you'd like to see more X-Power products available in the states
