My weight is 266, and when I'm at the gym they have the target heart range charts everywhere, and for my age, they say I should be working in the 115 - 153 (approx, don't remember exact) range with the lower half being the fat burning range. One of the machines I use even has a fat burning program on it, and it wants my target heart range at 118.

However, I'm assuming because of my weight and the effort it takes to move it, I can hit 145-155 really easily, without feeling like I'm working too hard (hard enough, but not over-exerting). I kind of like this pace and feel like I'd be getting less benefit by dropping the effort down to where the rate would be 118. I usually do 60 minutes for my workout all on these machines, usually at that 145-155 heart rate the whole time.

My primary goal is weight loss, my lean body mass is 60%, so I have plenty of lean body mass, so I don't need to build it up, and while cardio training is also important, my weight loss is my primary goal right now.

Any really knowledgable fitness afficianados or trainers or otherwise educated people out there that can advise me if it really is better to work out less intensely rather than more?