Stock brake pads interchangeable with Hawk HP+?
 

So I was planning on getting Hawk HP+ pads for the track and HPS for the street, but I have heard a lot about how HPS don't have a good initial bite in colder weather. So I am now thinking of keeping the stock pads for street but I'm not sure if they are interchangeable with the HP+, as in would I have to clean the rotors and re-bed the pads each time I switch between stock pads and the HP+ pads?

Also if anyone could comment on the HPS initial bite in cold weather that would be great.

The HP+ should work ok with the stock pads. If you're really worried about it, spray the rotor with a hose the night that you put the pads one. Let it sit overnight and rust. Once you start driving the next day, the new pads will wear away the rusted deposits from the old pad and you should be good to go. Ive never seen anyone have issues going between a stock pad and a not very aggressive aftermarket pad like the HP+

IME the initial bite of the HPS in cold weather is fine. I've had them on our Forester XT which is our dedicated winter vehicle for the last 3 years. Never had any problem with braking in the cold with them on the first stop or subsequent ones.

HPS are the absolute worst pads I've ever used. Soft pedal feel, zero tolerance for any kind of heat. I really don't understand what those pads are supposed to be about, they're way worse than most OEM pads for any kind of usage. Don't bother.

HP+ are about the highest coefficient pads I've ever experienced (including carbotech XP10). They won't handle temps as high as "real" track pads, but I never had any issues tracking my S2000 on street tires with them. Personally, I liked the low pedal effort required to get maximum braking, but some do not care for their grabbiness and feel it hinders ability to modulate (I've never felt that to be the case).
No issues swapping between OEM pads and HP+ for me.