Stealth Grow Cupboard

Hi all Im a Newbie first time grower and wondered what people thik of my first cabinet build any suggestions for impprovements are welcome.

Me and a few pals were unable to find a decent smoke for a while and decided to get a small grow going to see first hand what exactly ispossible. We decided that quantity wasn't an issue at this point with our limited space and resources and quickly decided that our focus should be on quality.

My main concern is what quality can we expect with three clones in this small space??

Also is 150w of MH Light enough for a space 70cm x 40cm x 60cm (HxWxD) and 3 clones???

Grow Cupboard Dimensions: H70 x W40 x D60
Lights: 2 x 150w Metal Halide with 1 red and 1 blue Bulbs/Lamps.
Air In: 4 x 12v Computer Fans.
Air out: 1 x 230v 3'' Fan
Filter: 1 x 4'' Odorsok

Temp: by Day(lights On) - 76-85 degrees F
Temp: by Night(lights Off) - 58-65 degrees F

Humidity: by Day 28%-38%
Humidity: by Night 30%-45%

Plant Strain: UK Cheese Clone

All Water Used Has Been Left to sit for 24-48hrs prior to use.

Any Tips or Advice would be greatly appreciated...