Hello,
Instead of having the title of my website displayed through an image, I’d like to use a web-font. I just need to make sure the text is going to have a specific width, because the design esthetic relies a lot on that.
Is it a good approach? Should I keep my image?
Regards,
-jj. 
I would just keep the image if you need the text to be spaced out a certain way, otherwise you may run into problems with different screen resolutions.
I’m not quite sure what you are asking exactly but you can’t really set a width on text and just expect it to fit. You can increase the font size and letter and word spacing and make it wider as required but there is not complete control over it.
If you want to keep your image you could use a gilder/levin image replacement technique and get some text in the html for accessibility.