It's not just about matching the max ranges of the missiles with those of the radars'. We have to realize that the outcome of every missile launch will depend heavily on the kill probability (KP) of that missile at launch. The 'KP' itself is dependent on a great many factors, e.g. the altitude at launch, the altitude of the target at launch, the speed at launch, the speed of the target at launch, the relative angular aspect of the target, even the prevailing weather and wind currents at the scene of the battle. The most important of these is the distance between the launching aircraft and the target. For simplicity's sake we will assume all the factors except distance to remain constant throughout this discussion. For range, it's very simple; the closer you are to the target at launch the higher your KP, until you hit the No Escape Zone. The No Escape Zone, simply put, is a range of distance with certain given conditions where, theoretically, the target cannot escape the missile and hence the KP is 100%. At times there is a minimum launch distance as well but it is usually negligible, e.g. reported 2km for the AIM-120. The KP at max range of the missile will be the lowest of all, barring at beyond max and below minimum ranges where it would be zero. Hence the reason why no one really expects an A2A missile to be launched at max range.
Let's take the AIM-120D as our example. It's max range is stated to be >160km. It's No Escape Zone is estimated to be around 70km. This tells us that, under certain given conditions, at beyond 160km you will have no chance of getting the kill, at around 160km you might get the kill but the probability of that happening will not be very encouraging (How much exactly? We won't know that anytime soon). As you move closer to the target the KP will increase. When you are around 70km away your KP will theoretically max out at 100%; the target will be inside your No Escape Zone. When will you launch the missile? That will depend on the situation in the air and the desired outcome from the launch. If you are looking for a kill, you would want to launch them at the lowest possible distance that you would be able to. Launching within the No Escape Zone, more often than not, will not be possible. You could also launch them at max range just to make sure that the two bogies dispatched by the enemy to intercept your strike package are made busy before they can disrupt your strike. This is where the man behind the machine comes into play.
The PL-15's and the SD-10's estimated max ranges are 150km and 100km under certain given conditions, respectively. Their No Escape Zones are unknown but we can very roughly approximate them from the available estimates for the AIM-120C and AIM-120D. For argument's sake, let us assume that the No Escape Zones for the PL-15 and the SD-10 are 30km and 60km respectively. With the 100km approximate max detection range of the KLJ-7V1 radars on the JF-17 Block 1s and remembering everything that I have mentioned above, it is clear to see that from the first point of detection at 100km till 60km the PL-15 will have a better chance of hitting the target than the SD-10. In fact, I am confident that the PL-15 will offer better KP at every possible launch distance than the SD-10, pretty sure that it will have a leg up the SD-10 in many aspects and not just the range.
In short, will the PL-15 be utilized to its max potential range on a Block1/2? No, but then most missiles seldom are. Will it be a better weapon to have than the SD-10 in an air battle when flying a block 1/2? Always.