Sonca halogen lamps?

[Velcro]

I was thinking about getting a Sonca halogen lamp for my Mag-Lite 3D (price around $4.50). My main question (and concern) about this lamp is; does it work well for adjustable focus flashlights (such as the Mag)? In other words, will the beam not have weird shapes, streaks and hotspots on places you wouldn't expect them?

Also, how do they compare to the Philips halogen lamps? I used a Philips halogen lamp in my Mag a while ago and the focus was very bad, practically useless.

Greetings,
Velcro