Inconsistent and missing styles

Firstly, if I use wkhtmltopdf there is an error reported on the page:
Error on line 3 at column 20: Expected '>', but got '[a-zA-Z]'.

So the issues are to do with TCPDF and DOMPdf

Both of these I put the style in the template file itself, because {{entity_print_css}} does nothing even though the print-style.css exists and setup as per instructions.

TCPDF outputs the PDF in a nice dont. Possiby the website font, I do not know, but its a suitable font to use. But then some styles get applied and some do not. I can put borders on tables cells, although the colour and padding is ignored. Padding I set is ignored. So although the font is OK, the general design is not good as I cannot style it at all.

So I switch to DOMPdf. This is much better for general styling. Looks like I can style most things. BUT it wont change the font. The font looks like Times New Roman.

So am I doing something wrong please, or are both PDF generators just lacking in CSS support?

Thanks