It's one thing to be concerned about brand new gear not based on existing designs or from no-name manufacturers with no history.... the 1054z is definitely not that. It may not be built to last 20+ years, but it has been thoroughly tested and investigated - you will certainly not be the first to consider buying one and there is TONS of information on this very forum as to hacking, servicing, and common failure modes. It is not the only 'new' scope that can claim that history, either.
There's also the fact that there are plenty of reputable companies that farm out the design or manufacture of their lower end (lower bandwidth) units to others and have run into trouble because of it, even when charging a premium for the name.... so I'm not sure trying to go with an inexpensive Aglient or LeCroy would actually be better than a Rigol in terms of reliability or usability, and it would certainly be pricier for the performance. I also don't think the probes are going to make a huge difference if the bandwidths are under 50MHz - seems like there are a lot of decent options for low bandwidth probes.
Have a look around for some of the older scopes from Tek, LeCroy, HP-Agilent, etc. as you may be able to get a pretty nice deal (comparable price to the default rigol or a bit less) in the under 200MHz bandwidth category, but I don't think they're necessarily better choices unless you have a specific feature to look for. Is a 15-25 year old warhorse really going to last the next 10 years any better than a 1054z.... so I wouldn't say so.... though maybe they'll be better off in 20 years time. Personally, I really like some of the newer features available on more modern scopes, I like the expanded memory depths and I find the display to be more descriptive (more relevant data on the screen), among other things. It's as much personal preference as anything regarding those, if you don't have a specific use for them.