Mac Mail Or Maxbulk Mailer?

For emailing existing clients-NOT SPAM

[akmac]

I send out a newsletter periodically to my customers, as well as special offers and the like. Currently, I use Maxbulk Mailer for sending to the group. My question is:

Can I just use Mac Mail instead?

If I did, what problems might this cause?

How many recipients can mac Mail handle?

The reason I'd like to is that I'm more familiar with Mac Mail-and it will be easier to use 1 mail program than two.

Are their different ways that the programs function that may or may not influence spam checkers? I have a list of under 1500 folks that are all opt-in.

[weeks]

I use the Maxbulk Mailer because every system (Outlook, Mac Mail, Entourage) on my machine I used gave my ISP provider fits.