I was not able to find a set uptime guarantee, or even a list of their past performance on their site.  The site is not in English by default, however, and the translation did not come across extremely well.  It is possible that they list some information about it but I wasn't able to find where.

Despite that, I did not find any customers complaining of frequent downtime or anything, so this likely is not an issue.  I would not be concerned because of the fact that they do seem to focus on high quality hardware and data centers.

This company has a lot of different hosting packages to choose from.  They seem to really push combining their hosting with their other services, which some people may see as a negative.  For example, they offer hosting plus email management.  Most hosting companies include email support as a standard feature, but Aruba.IT seems to want to charge extra for it.

They have Linux and Windows servers available, which is nice.  They also include a domain name with just about every package.  The bottom line here is that they have everything you'll need to get your site up and hosted properly, even if it is sometimes confusing.

They really don't provide too much information about the technical support they offer.  It is there 24/7, which is good.  They have a phone number listed, but little else.  It seems like they have a ticketing system as well, but I could not confirm that.

The prices they offer are higher than what you would expect to see.  It seems like they bump their prices up and try to include other services in the packages to justify it (such as the email or DNS management).  The prices are not so far out of the ordinary that they will be a major problem for most companies, but it is still a concern.