Not sure anyone could provide a simple yes/no .... how about a maybe? Why? You've not shared what SiteGround offers under their 'GrowBig plan' - tech specs.
Appears SiteGround is trying to keep up with other hosting providers in the area of Virtual Private Systems ... ie, dedicated servers to one customer ... they are famous, for their $4.95 a month plans ... or they were at one point in time many years ago.
According to this:
https://www.siteground.com/web-hosting.htm
The GrowBig is $5.95 a month .... hmmmmm ... devil might be in the details ... which many times isn't shown on public web pages.
"If you need more resources and premium features in addition to the
essential features then we recommend the GrowBig Plan. This plan is
designed to accommodate either a single more heavily-trafficked website
or multiple average-size websites."
Can't translate that for ya ... think you're gonna have to contact SiteGround folks and pose the very same question to them ... just to see what they say.
See their 'GoGeek' plan? That's more expensive and here's what they say about it ...
"If you have a really heavily-visited or resource-intensive website then
the GoGeek plan is your best option. The GoGeek customers are hosted on
instances, where fewer users share the server resources."
Uhhh ... hosted on instances where fewer users share the server resources is key there.
Typical VPS's are dedicated machines .... with options for memory/space/throughput, etc. ... *not shared*.
Does SiteGround of any tool for you, the customer, to get an idea of how your instance is performing?
In there 'Uptime' tool there is a graph they brag upon that shows 'response time' .... but, as you've said, you've never had all 40 participants on your site at one time. Hey, here's an idea ... do something with the moodle where you are inviting 1/2 of your participants to do something .... something memory intensive? or process intensive? Then check the 'response time' chart. Hmmmm how about a little session with BBB? The heavy processing would be done on the BBB box/service but you are using via Moodle.
Might check into BBB itself ..... beginning here:
http://docs.bigbluebutton.org/support/faq.html#what-are-the-minimum-bandwidth-requirements-for-a-user
One thing you cannot control is students connections to your site - and thus BBB.
Wait a day or two then do something on your moodle and invite 3/4's of your users to participate ... then check the 'response time' chart.
Now if you had access to command line one could run top ... if you had access to that ... and see realtime how things were looking. May not have command line access or if you do, may not have access to CLI tools like 'top'. :\
So bottom line .... for me, I'd say 'maybe'.
Anyone else in these forums host with SiteGround?
'spirit of sharing', Ken