Gislaved Speed 506

Has anyone heard of these tires and are they a decent tire?
I have a chance to buy these Speed 506 tires which are ZR rated at a very attractive price. Your input would be appreciated.

I've heard of Gislaved before but don't have detailed info on this particular tire. From what I've heard their emphasis is on snow traction so may be a good choice for someone in a snow area. Make sure they're not snow tires that are exclusively designed for winter because snow tires will wear out very quickly if used all year round.

Gislaved Speed 506 these are amazing tires I have them on my 1996 Volvo 960. They handle amazingly never had any problem with them. The tires stick to the ground like glue especially at speeds of 130mph still handles great.