For low temperature cooking in a combi oven I have done chicken thighs at 165F for 5 hrs @ 100% humidity after 20 min @ 320F to get them up to temperature. After they were cooked I let them cool off a little, dried off the surface, painted them with evaporated skimmed milk, and browned them at 525F and 10% humidity for 3 min. The sugar and protein in the milk enhances the Maillard reaction and you get a nice result without overcooking. Without the milk you get very little browning of the skin due (I think) to the high fat, low protein, low sugar surface.
Interesting results. A combi oven can be used as a substitute for sous vide cooking if you use it in steam mode.
Obviously, a combi oven can be used to cook bag-sealed sous vide. However, in most cases you can also just cook the same food in open pans in a combi-oven and get results that are comparable to sous vide.
The only things that don't work this way are oxygen dependent - for example, endives and artichokes braise nicely sous vide (in a bag) and stay light colored, whereas they are prone to browning otherwise.
Combi oven "pseudo sous vide" is great if you have a combi oven but do not have a vacuum packer.
Note that combi ovens are NOT as accurate as a laboratory water baths - they typically vary by plus or minus a couple degrees during the thermostat cycle. This is not critical for a lot of sous vide cooking, but can be for some things - like salmon mi-cuit where a few degrees makes a difference. It also matters for rare red meat.
Best approach is to check your combi oven with a very good digital thermometer.
I do chicken thighs at much lower temperature 145F - either sous vide, combi oven in steam mode for 2 hours. I have tried as low as 136F (still within FDA guidelines).
Ultimately this is just personal preference. 5 hours is a long time, unless you have really tough chickens.
The milk is a good trick for browning. A sweet sauce will also carmelize well - for example teriyaki sauce works very well. Any other sweet sauce that will contribute sugar for carmelizing will work, such as a sweet barbeque sauce. In order to get the browning effect you want the sauce to be thin - thinning with water works well.
If these are skinless thighs that is a good approach. If you have the skin on then you can brown with a very hot radiant broiler / salamander, or a blow torch.