I am also buying a mobile at 10k. I have checked Motorola Fire XT, HTC Explorer and LG Optimus Net extensively in the showrooms, and I am personally going for LG Optimus Net P690.
Motorola Fire XT has the best hardware spec among these 3, so I was quite biased towards this one. However, on seeing the phone personally, I didn't like it. Though it has the largest screen size among these 3, yet, you wouldn't believe that it was the screen that put me off. Visibly low resolution, less responsive. Lacks the crispiness. Apart from that, some reviews are bad too. Custom ROM/kernel development and support is also poor.
So, there remains LG Optimus Net P690 and HTC Explorer. Both have good chipsets, Optimus has better processor (800MHz vs 600 MHz), both have same GPU, Optimus has a better battery(1500mAh vs 1230mAh), Optimus has higher internal memory (150mb vs 90mb) - you know how important it is if you have spent some time in the forums. The screen on both, though, theoretically same [3.2"], LG wins here because of more crisp display, and Explorer has less 'available' screen due to touch buttons. Optimus Net has way better development and support as compared to HTC Explorer. So, I personally preferred LG Optimus Net, after seeing both of them. The only advantage of HTC Explorer is that it is definitely better looking and has better-speed-3G (14mbps vs 3.6mbps), and approx. Rs. 700 less in price.
In any case, the final decision is always yours.
However, if 3.6mbps 3G speed appears sufficient for you, and you do not care about external looks, LG Optimus Net P690 is the way to go.
Edit: I forgot to mention that LG Optimus Net has a camera flash, though I really doubt its power, while HTC Explorer doesn't have. [Personally, I have zero importance to the camera while buying a mobile, and is not at all a deciding criteria]
