I have used Pair Networks as a host for my sites for some time. It's been so long that I actually had to look it up to see how long. It turns out that it's been more than two years already. In all that time, I have had hardly a hiccup. I like that. It means that I don't have to worry about much when it comes to the sites I run on their servers.
When it comes to email, however, it takes a bit more work. It isn't that it's difficult, it just isn't as simple a process. This is because email can quickly become a burden. However, there are some really simple processes you can put in place to deal with it and make it much simpler to handle.
One way to deal with mail at Pair is to work with procmail. Unfortunately, the use of procmail can be challenging. It's not hard, exactly, but it is a bit complex. You have to create recipes that will process your mail how you want it. The cool thing is that this gives you lots of control over just what happens with your mail. The bad thing is that it can take a lot of work to keep up with this process, and nobody likes to take time out of their day to do this. If you want to do so, you can make this just about as complicated as you like. Because this subject is so complex, I'm not going to go into it here. If you want to try it, just search and you'll find lots of information that can keep you busy for hours. Days, even.
The next step is to make use of one of the best spam filters available - Google - by forwarding your email to them, and letting it return the mail to you for reading. All it takes is a couple of addresses and forwarding rules, as well as a Gmail account.
To start with, I would create a mailbox at Pair. The mailbox is never never revealed to the public. I typically create something that is difficult to guess. It can be something very, very difficult to guess, like combinations of letter and numbers, but that is up to you. The point is that the mailbox will be unlikely to receive any spam on its own simply by dictionary-style spam attacks.
Next, you create an email address that is used in a recipe for forwarding to Gmail. This is the address you use when you give it out. In this way, if you ever need to change the address, you change this address - but your real address is safe and sound. All that needs to change is an update to the forwarding recipe. When mail is received at this address, it is forwarded to your Gmail address.
In Gmail, you create a filter that simply forwards mail back to Pair, but not to the forwarding address, as that would create a loop. Instead, it forwards it back to the mailbox address. In this way, all mail that comes in is processed by the Gmail spam filter prior to your mailbox ever seeing it, as you have never given out the mailbox address itself, so it should never have any spam in it.
If you give out the mailbox address, it defeats the purpose. If you use your Gmail address for other reasons, you may want to update the filter so that only mail coming from the forwarding address is returned to Pair. Or you may even want to use Gmail exclusively to read mail, and not bother sending mail back to Pair (mail reading would likely be faster in this case, so you don't have to depend on two forwards). Still another option would be to use Google Apps Standard Edition, which is free for up to 50 accounts, and you can eliminate Pair entirely from the email equation!