Adding High Output T5's

I've got a 3x3x4 area with 13 seedlings going, a 400W MH for veg, and a 400W HPS ready for flower.
I'm thinking that I might like to upgrade a little and add two High Output T5 2 foot 4 lamp Growbrights to either side of the cabinet.

First off is this necessary and secondly would those T5's be best served as FLOWERING bulbs working with the MH during veg or...

...ALL light be VEG type lighting and then switch all bulbs to FLOWER type when the time comes?

Thanks all...

Wondering if anyone had thoughts on adding these lights...

You're better off upgrading to a 600w MH and HPS system, cheaper in the long run.

Just speaking as someone that owns both T5HO lights and HID lights.

I've got a 400MH and 400 HPS...

you're saying it's better just to upgrade to a 600W than to add the T5's?

Yup. You'll practically double your light output just moving to a 600w system.

T5HO is good for bout 200-250 watt grows, once you hit 400w+ you need to be using HID

Just upgrade to a larger 600w system, and keep the 400w system for another smaller grow for like 9 or so plants, as you're stretching it thin with 13 plants and 400w as it is.