On the advice, listen to your dealer for the lamps. This given you are able to detect if they know their lamps or if they are just attempting to sell you some stuff. Most likely they have either play tested what they might recommend or not recommend as an alternative and will further stand by what they sell should it not work out so well for you. In a specified lamp for the fixture, this is the lamp the fixture was designed to use or was later tested in what’s listed the fixture by spec can use. That’s important also in detail by way of should something other than the specified lamp be in the fixture, any damage the lamp does say to a reflector that could cost as much to replace if not more than the lamp done, might not be covered under warranty.
In other words, ask questions of those you buy the lamps from and fixture from, express your concerns say on budget and what is going to work. All it takes is one lamp taking out a reflector should it blow up and it becomes very costly to get it running again. On the other hand in expecting you are most likely talking about say a MSR 575/2 with it’s variants the MSR 575 and MSD 575 (all with their own advantages and disadvantages but would work), that is a lamp that has been on the market a long time now. Most manufacturers, Made in China or Domestic or Name Brand will have in their own way mastered that lamp to the extent they can. Often the major difference between brands is in output and color temperature when you get into matching up one brand of lamp to another and even in the initial first few hours where the lamp is stabilizing itself. In you getting what you pay for, at times a lamp might take hours to get to it’s design spec and fluctuate wildly while getting there. Once at it’s operating output and color temperature, in matching up to and playing nice with lamps of other brands, at times the off brand or even lot number of them won’t match up. While Phillips prices are often a bit more on lamps, for certain lamps from them at least it’s worth it as opposed to other less reliable lamps both for output and lamp life. This clearly not to say that Phillips lamps are perfect, wouldn’t touch one for a Mac 2K. On the other hand, it’s the best 700SA lamp on the market. For a MSR 575/2, that’s a fairly wide open market in what’s cost effective. Certainly won’t go wrong with a Phillips lamp - it is a very safe bet. Other brands one might find are just as good in this lamp however given it’s age and time to refine their versions.
This concept of alternate brands to the extent that if your inventory is the same lamp, even if by far different in output and color temperature from the bench mark Phillips lamp, if all the fixtures you see are say dim in comparison, remove what you compare them to and they are bright as day.
Reliability of the lamp than is the factor to weigh against price. Name brand lamps are normally reliable, other brands can also be but are not always - see above on dealer recommendations and experience. One brand does not work so well for you? Try another perhaps over time. Take copious notes on each lamp and the lamp hours. Track all info available, it can mean free lamp replacements at times if lot number problems or individual lamps that don’t live up to a reasonable at least 2/3 expected lamp life. On the other hand, no matter the brand there is always a 10% at least of all which fail. That’s life in the world of a high output lamp.
Wouldn’t say I would go for something that you know is way too cheap for your investment, but might go for something that seems with recommendation sufficient for your needs.
Me, I don’t use this lamp, I use another premium brand that after testing is just as reliable and good. Still stock the Phillips in this type but only for resale or when I run out. Good lamps, other good lamps available.
And no, I will not say one brand over another because as said, budget plays a factor in choosing beyond what one or another person decides is best for them.