isnt this a rohs solder, the unleaded one, very hard to unsolder i heard?
I don't know about that specific WBT solder, but there is a lead-free solder available on S.P.Road that is fairly smooth-flowing with a 40W Goot soldering iron. This is called SACX 0307, and it is mostly pure tin with a small fraction of Silver, Copper and Bismuth.
I have assembled a couple of MyRefs as well as some other smaller boards with this solder, and it seems to work well, though the joints have a dull grey finish even when they're good. You will need higher iron temperatures and wattage, but reworking is fairly easy with a desolder pump or wick, once you get used to the higher temperatures and viscosity.
Pros:
1) It does work even on surfaces containing lead, and generally easily wets all the conventional metals normally encountered in electronics soldering - tin, copper, brass, nickel, kovar, silver, gold, etc.
2) Compatible with older Sn-Pb solders, so it can be used for repair or rework of existing equipment.
Cons:
1) Higher temperatures make it easier to damage or delaminate some cheap PCBs. Don't even try to repair Marantz CD players with this solder.
2) Ditto for polystyrene and certain other expensive film/foil caps - they'll get damaged if you linger with the tip for more than 3-4 seconds.
3) Large ground planes and big electrolytics require higher wattage.
4) The solder is expensive, at Rs.1500 for 500 gms, which is usually the minimum reel size available.