I think you should get the Intel one as it is based on a better Chipset, Z75. However, I don't think you will get any performance advantage when used with an i3 processor due to the fact that i3 does not support any Turbo Boost frequency. With Z75 motherboard and a non-K i5 processor, you can do some minor overclocking by increasing Turbo Boost frequency of the Processor, making it runs at higher speed during high CPU load which is not possible with any B75 chip based motherboard. However, since i3 does not support any Turbo Boost, it will behave similarly in both the motherboards.
Any local PSU is never recommended. You can get a Iball/Intex/Frontech cabinet w/o PSU and get a good PSU like Antec BP300 @ 1.8K.